1. Field of the Invention
The present invention relates to journal bearings and, more particularly, to self-lubricating journal bearings incorporating lubricant plugs and coolant channels.
2. Description of the Prior Art
Journal bearings are conventionally formed of fiber or babbit materials. Machines such as those used to hot roll large billets in steel mills utilizing rolls and shafts weighing many tons and are subjected to additional bearing forces of many more tons from the reaction of the rolling process. In many of these machines, the rolls are supported on sleeve or journal bearings which may be made from bronze or babbit metals or from composite structures such as fiberglass mats impregnated with epoxy resin.
In steel mill rolling applications, the roll bearings cannot be lubricated by the well established principles of lubrication engineering because of the high temperatures of the billets of steel which are in close proximity to the bearings. Current practice is to spray the bearing housings with cooling water and to flood the bearings with water for the purposes of cooling and generating a hydrodynamic lubricating film. The bearings wear rapidly and substantial time and cost is involved in the necessary periodic bearing changes.